export function hasClass(el, className) {
  let reg = new RegExp('(^|\\s)' + className + '(\\s|$)')
  return reg.test(el.className)
}

export function addClass(el, className) {
  if (hasClass(el, className)) {
    return
  }

  let newClass = el.className.split(' ')
  newClass.push(className)
  el.className = newClass.join(' ')
}

export function getData(el, name, val) {
  const prefix = 'data-'
  name = prefix + name
  if(val) {
    return el.setAttribute(name, val)
  }else{
    return el.getAttribute(name)
  }
}

let elementStyle = document.createElement('div').style

 let vendor = (() => {
   let transformNames = {
     webkit: 'webkitTransform',
     Moz: 'MozTransform',
     O: 'OTransform',
     ms: 'msTransform',
     standard: 'transform'
   }

   for (let key in transformNames) {
     if (elementStyle[transformNames[key]] !== undefined) {
       return key
     }
   }

   return false
 })()

 export function prefixStyle(style) {
   if (vendor === false) {
     return false
   }

   if (vendor === 'standard') {
     return style
   }

   return vendor + style.charAt(0).toUpperCase() + style.substr(1)
 }
